panll_gui.affine

// SPDX-License-Identifier: AGPL-3.0-or-later
// PanLL GUI — AffineScript TEA Interface
// Underpinned by Cadre Router (Affine Stack Implementation)
//
// Purpose: Provide a formally verified, resource-safe interface for the
// PanLL Panel Layout Language — Mission Control for the hyperpolymath ecosystem.
//
// Nature: AffineScript TEA loop where Model and Msg are consumed linearly
// to ensure state transition integrity.

// ── PanLL Panes ───────────────────────────────────────────────────────────

enum PanLLPane {
  PaneL, // Symbolic
  PaneN, // Neural
  PaneW, // World (Barycentre)
  Vexometer
}

// ── Model ───────────────────────────────────────────────────────────────────

/**
 * PanLL GUI Model.
 * history_depth tracks the navigation stack size.
 */
struct Model {
  current_pane: PanLLPane,
  history_depth: Int
}

// ── Msg ──────────────────────────────────────────────────────────────────────

enum Msg {
  Navigate(PanLLPane),
  PopState
}

// ── TEA Logic ────────────────────────────────────────────────────────────────

/**
 * Initial state: PaneW (Task Barycentre) with no history.
 */
fn panll_init() -> Model {
  #{
    current_pane: PanLLPane::PaneW,
    history_depth: 0
  }
}

/**
 * Affine TEA Update function.
 * @linear annotations enforce that every state transition is accounted for.
 * Underpinned by Cadre Router: navigation pushes current to stack.
 */
fn panll_update(@linear msg: Msg, @linear model: Model) -> Model {
  match model {
    { current_pane: c, history_depth: h } => {
      match msg {
        Navigate(new_pane) => {
          // Consume old model, produce new model with incremented history depth
          #{
            current_pane: new_pane, 
            history_depth: h + 1 
          }
        }
        
        PopState => {
          if h > 0 {
            // Return to PaneW if stack has items
            #{
              current_pane: PanLLPane::PaneW, 
              history_depth: h - 1 
            }
          } else {
            // No-op transition: return model as-is
            #{
              current_pane: c, 
              history_depth: 0 
            }
          }
        }
      }
    }
  }
}

/**
 * View function: Renders the current pane name.
 * Owned model prevents codegen errors with refs.
 */
fn panll_view(model: Model) -> String {
  match model.current_pane {
    PaneL     => "PANE-L: SYMBOLIC MASS (Strict Logic & Constraints)",
    PaneN     => "PANE-N: NEURAL STREAM (Inference Manifold)",
    PaneW     => "PANE-W: WORLD BARYCENTRE (Shared Task Canvas)",
    Vexometer => "VEXOMETER (Cognitive Friction Monitor)"
  }
}

/**
 * Subscriptions function.
 */
fn panll_subs(model: Model) -> String {
  "None"
}